• Journal of Biomedical Engineering Research
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• v.28 no.6
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• pp.803-810
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• 2007

Although synthetic aperture focusing techniques can improve the spatial resolution of ultrasound imaging, they have not been employed in a commercial product because they require a real-time N-channel beamformer with a tremendously increased hardware complexity for simultaneous beamforming along M multiple lines. In this paper, a hardware-efficient beamformer architecture for synthetic aperture focusing is presented. In contrast to the straightforward design using NM delay calculators, the proposed method utilizes only M delay calculators by sharing the same values among the focusing delays which should be calculated at the same time between the N channels for all imaging points along the M scan lines. In general, synthetic aperture beamforming requires M 2-port memories. In the proposed beamformer, the input data for each channel is first upsampled with a 4-fold interpolator and each polyphase component of the interpolator output is stored into a 2-port memory separately, requiring 4M 2-port memories for each channel. By properly limiting the area formed with the synthetic aperture focusing, the input memory buffer can be implemented with only 4 2-port memories and one short multi-port memory.

• Journal of Microbiology and Biotechnology
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• v.7 no.3
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• pp.204-208
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• 1997

Aureobasidium puliulans possesses the capacity for simultaneous formation of fructosyltransferase and glucosyltransferase in various sugar media including sucrose, maltose, glucose and fructose. Among them, sucrose (300 g/1) was the most suitable carbon source for fructosyltransferase production, while fructose (100 g/1) gave the maximal production of glucosyltransferase. There existed a critical concentration for the optimal formation of enzymes in sucrose, glucose and fructose media. By contrast, no effect of maltose concentrations up to 300 g/1 was observed. The specific activity of the glucosyltransferase on maltose medium was highest during the early period of fetmentation, after which a sharp decrease occurred, whereas fructosyltransferase activity on sucrose medium maintained a nearly constant rate for a given culture period. Concomitant production of fructosyltransferase and glucosyltransferase was investigated with different combinations of lower concentrations of sucrose and maltose. Maltose supplementation in sucrose media and sucrose addition to maltose media enhanced the activity ratios of fructosyltransferase to glucosyltransferase as compared to that of non-supplemented media. Several polymers and surfactants were added in an attempt to enhance enzyme production, and supplementation of polyoxyethylene-sorbitan monolaurate (Tween 20) promoted fructosyltransferase production by 20%.

• Korean Journal of Head & Neck Oncology
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• v.35 no.2
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• pp.31-34
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• 2019

Lemierre's syndrome is rare disease characterized by anaerobic sepsis, internal jugular vein thrombosis, septic emboli that resulted from head and neck infection. Lemierre's syndrome has significant morbidity, so immediate, accurate diagnosis and treatment is needed. It is necessary to perform contrast-enhanced computed tomography (CT) for diagnosis. Systemic antibiotics is recommended, and surgical interventions, anticoagulation may beis considered for treatment. We report misdiagnosed case as a simple deep neck infection on initial ultrasonography with simultaneous abscess aspiration but finally diagnosed and treated internal jugular vein thrombophlebitis (Lemierre's syndrome) on CT scan. We report a case of a 45-year-old patient, who was diagnosed with a simple deep neck infection and treated with simultaneous abscess aspiration, but finally diagnosed and treated internal jugular vein thrombophlebitis (Lemierre's syndrome) on CT scan.

• Journal of Microbiology and Biotechnology
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• v.23 no.1
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• pp.99-105
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• 2013

In this study, nitrous oxide ($N_2O$) emission was compared between the operations of two different sequencing batch reactors, conventional sequencing batch reactor (CNVSBR) and simultaneous nitrification and denitrification sequencing batch reactor (SND-SBR), using synthetic wastewater. The CNV-SBR consisted of anoxic (denitrification) and aerobic phases, whereas the SND-SBR consisted of a microaerobic (low dissolved oxygen concentration) phase, which was achieved by intermittent aeration for simultaneous nitrification and denitrification. The CNV-SBR emitted 3.9 mg of $N_2O$-N in the denitrification phase and 1.6 mg of $N_2O$-N in the nitrification phase, resulting in a total emission of 5.5mg from 432mg of $NH_4^+$-N input. In contrast, the SND-SBR emitted 26.2mg of $N_2O$-N under the microaerobic condition, which was about 5 times higher than the emission obtained with the CNV-SBR at the same $NH_4^+$-N input. From the $N_2O$ yield based on $NH_4^+$-N input, the microaerobic condition produced the highest yield (6.1%), followed by the anoxic (0.9%) and aerobic (0.4%) conditions. It is thought that an appropriate dissolved oxygen level is critical for reducing $N_2O$ emission during nitrification and denitrification at wastewater treatment plants.

• Journal of Korea Multimedia Society
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• v.22 no.9
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• pp.1000-1010
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• 2019

Image semantic segmentation and dehazing are key tasks in the computer vision. In recent years, researches in both tasks have achieved substantial improvements in performance with the development of Convolutional Neural Network (CNN). However, most of the previous works for semantic segmentation assume the images are captured in clear weather and show degraded performance under hazy images with low contrast and faded color. Meanwhile, dehazing aims to recover clear image given observed hazy image, which is an ill-posed problem and can be alleviated with additional information about the image. In this work, we propose a deep multi-task network for simultaneous semantic segmentation and dehazing. The proposed network takes single haze image as input and predicts dense semantic segmentation map and clear image. The visual information getting refined during the dehazing process can help the recognition task of semantic segmentation. On the other hand, semantic features obtained during the semantic segmentation process can provide cues for color priors for objects, which can help dehazing process. Experimental results demonstrate the effectiveness of the proposed multi-task approach, showing improved performance compared to the separate networks.

• Nuclear Engineering and Technology
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• v.51 no.6
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• pp.1610-1615
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• 2019

Positron emission tomography (PET)/magnetic resonance (MR) scanning has the advantage of less additional exposure to radiation than does PET/computed tomography (CT). In particular, MR based attenuation correction (MR AC) can greatly affect the image quality of PET and is frequently obtained using various MR sequences. Thus, the purpose of the current study was to quantitatively compare the image quality between MR non-AC (MR NAC) and MR AC in PET images with three MR sequences. Percent image uniformity (PIU), percent contrast recovery (PCR), and percent background variability (PBV) were estimated to evaluate the quality of PET images with MR AC. Based on the results of PIU, 15.2% increase in the average quality was observed for PET images with MR AC than for PET images with MR NAC. In addition, 28.6% and 71.1% improvement in the average results of PCR and PBV respectively, was observed for PET images with MR AC compared with that with MR NAC. Moreover, no significant difference was observed among the average values using three MR sequences. In conclusion, the current study demonstrated that PET with MR AC improved the image quality and can be help diagnosis in all MR sequence cases.

• Journal of Fashion Business
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• v.27 no.6
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• pp.47-65
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• 2023

The purpose of this study is to derive the future-oriented characteristics Sonia Delaunay presented at the time based on the identity and modernity shown in her works and diverse activity. The scope of study spans from 1907 to the start of World War II and includes both applied and fine arts, with a focus on textiles and fashion. The research method is a literary study that includes old documents, exhibition booklets, and explanations from museum curators. The visual materials are actual works observed at exhibitions and digital images of various exhibitions. As a result of the research, she was a practitioner who expressed her identity in marriage, artwork, textiles, and fashion. In order to embody her design and express modernity, she showed geometric and modern motifs and she incorporated a sense of bright color and modernized light into her work by following the principle of simultaneous contrast in color. Additionally, she applied Hungarian embroidery techniques to simple materials and created geometric abstraction with her simultaneous colors, which contributed to both originality and the mass production of textile design. The future-oriented characteristics she presented are the dynamism of modern rhythm, the expansion of convergence and collaboration, the innovation of new production and exhibition, the media of consumer society, and the femininity of modern life. She recognized the mass consumer society and mass production of the early 20th century and actively utilized various media and genres to evoke a dynamic sense necessary for modern life and presented a design to be seen as a modern woman.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.1
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• pp.55-60
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• 2011

The most basic algorithm in SLAM(Simultaneous Localization And Mapping) technique of mobile robots is EKF(Extended Kalman Filter) SLAM. However, it requires prior information of characteristics of the system and the noise model which cannot be estimated in accurate. By this limit, Kalman Filter shows the following behaviors in a highly uncertain environment: becomes too sensitive to internal parameters, mathematical consistency is not kept, or yields a wrong estimation result. In contrast, $H_{\infty}$ filter does not requires a prior information in detail. Thus, based on a idea that $H_{\infty}$ filter based SLAM will be more robust than the EKF-SLAM, we propose a framework of $H_{\infty}$ filter based SLAM and show that suggested algorithm shows slightly better result man me EKF-SLAM in a highly uncertain environment.

• Journal of Veterinary Clinics
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• v.38 no.3
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• pp.120-126
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• 2021

Intradermal skin test (IDST) is generally considered a useful tool in identifying causal allergens in canine atopic dermatitis. Currently, multiple allergen simultaneous test (MAST), an in vitro testing method for allergen-specific immunoglobulin E, is being used as an alternative method. However, there are no reports comparing the IDST and MAST results in the same dogs. This study compared the results of both tests to evaluate the agreement and correlation between them. The sensitivity, specificity, and accuracy of the MAST were 76.2%, 64%, and 66.7%, respectively. Moderate positive predicted value (PPV, 50-75%) or high sensitivity (80-100%) were identified for indoor allergens, such as cat epithelia, house dust, and house dust mites. In contrast, high negative predicted value (NPV, 93.3-100%) and specificity (60-100%) were observed for environmental allergens and fungi. Although the agreement between IDST and MAST for all allergens was fair (κ = 0.301), that for each allergen was poor (κ < 0.01), except for birch (κ = 0.158). Spearman's rank correlation analysis revealed a low correlation between the MAST and IDST results (ρ = 0.308, p = 0.001). As compared to the IDST results, the MAST results did not identify the causative allergens sufficiently. IDST may not be performed for environmental allergens and fungi with high NPV and specificity if the MAST result is negative, but it may have to be performed for indoor allergens with moderate PPV and high sensitivity when the MAST result is positive.

• Journal of Broadcast Engineering
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• v.13 no.5
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• pp.651-661
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• 2008

This paper proposes a novel contrast enhancement (CE) algorithm for color images using the modified error diffusion (ED). After conventional color histogram equalization (HE), artifacts such as false contours are produced in the contrast enhanced image. The proposed CE algorithm using the modified ED consists of two parts: CE and ED. In the first part, a low-contrast input image is enhanced by the conventional HE method. In the second part, we use the modified ED algorithm. The inputs of the second part are the average and scaled difference images of the original color input image and the HE image, in which the scaled color difference image is diffused by the ED algorithm. In the proposed algorithm, the modified ED algorithm reduces the artifacts produced in the HE image, and increases the number of color levels. Computer simulations with a number of low-contrast color images show the effectiveness of the proposed CE method in terms of the visual quality as well as the probability mass function. It can be used as a post-processing for CE with simultaneous artifact reduction in various display devices.